over the past 20 years, scientists have been using technology on nature to improve food supplies. they are producing genetically modified (GM) foods by modifying, or changing, the genes of plants and animals.Genes are the codes in the cells of every living thing that determine the way they look and grow. In humans, genes determine characteristics such as the color of our eyes and how tall we are. By changing the genes of plants, scientists can cause crops to produce more, become nutritional value.